header{
  width: 100%;
  height: 60px;
  background: #222;
  min-width: 1200px;
}
.header_main{
  width: 1200px;
  margin: 0 auto;
  height: 60px;
  display: flex;
  justify-content: space-between;
  line-height: 60px;
  color: #fff;
}
.header_left{
  font-size: 22px;
  font-weight: 500;
  cursor: pointer;
}
.header_left:hover{
  text-decoration: underline;
}
.header_right{
  color: #b4b4b4;
  display: flex;
}
.header_right>div:hover{
  color: #fff;
  text-decoration: underline;
}
.header_right>div{
  cursor: pointer;
  margin-left: 40px;
}
.biaodan{
  width: 1200px;
  margin: 20px auto;
}
.photo{
  width: 50px;
  height: 50px;
  border-radius: 50%;
}
.login {
  display: none;
}
.mtbtn{
  width: 70px;
  background: #222;
  margin:0 !important;
  position: absolute;
  top: 60px;
  left: 0;
  display: none;
}
.user{
  position: relative;
  display: none;
}
.user:hover .mtbtn{
  display: block;
}
.mtbtn div{
  width: 100%;
  height: 40px;
  line-height: 40px;
  color: #fff;
  padding: 0 5px;   
  font-size: 13px; 
}
.mtbtn div:hover{
  background-color: #525252;
}
.myphoto{
  display: none;
}